We are developing a strategy to make corrections of the amplitudes and phases of the structure factors computed from electron images of single particles. Our computational procedure has proven effective in determining the zeros of the contrast transfer function and thus the defocus value of the image. Defocus determination is used to correct the phase reversal of the structure factors. We attempted to use x-ray solution scattering to determine the scattering profile of the particles with which we would correct for the amplitudes of the computed structure factors. Initially, we collected low angle solution scattering data in the range of 300 to 50 E using a multi-layer crystal and then high angle data in the range of 100 to 5 E. We used a better positionally calibrated monochromator crystal for data collection at resolution ranges from 400 to 13 E and from 50 to 4 E. We are able to determine the amount of amplitude contrast and the extent of damping in the computed transforms of our 400 keV images P22 phages.
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